1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2005 Intel Corporation
4  * Copyright (C) 2009 Hewlett-Packard Development Company, L.P.
5  *
6  *	Alex Chiang <achiang@hp.com>
7  *	- Unified x86/ia64 implementations
8  *
9  * I/O APIC hotplug support
10  *	Yinghai Lu <yinghai@kernel.org>
11  *	Jiang Liu <jiang.liu@intel.com>
12  */
13 #include <linux/export.h>
14 #include <linux/acpi.h>
15 #include <acpi/processor.h>
16 
get_madt_table(void)17 static struct acpi_table_madt *get_madt_table(void)
18 {
19 	static struct acpi_table_madt *madt;
20 	static int read_madt;
21 
22 	if (!read_madt) {
23 		if (ACPI_FAILURE(acpi_get_table(ACPI_SIG_MADT, 0,
24 					(struct acpi_table_header **)&madt)))
25 			madt = NULL;
26 		read_madt++;
27 	}
28 
29 	return madt;
30 }
31 
map_lapic_id(struct acpi_subtable_header * entry,u32 acpi_id,phys_cpuid_t * apic_id)32 static int map_lapic_id(struct acpi_subtable_header *entry,
33 		 u32 acpi_id, phys_cpuid_t *apic_id)
34 {
35 	struct acpi_madt_local_apic *lapic =
36 		container_of(entry, struct acpi_madt_local_apic, header);
37 
38 	if (!(lapic->lapic_flags & ACPI_MADT_ENABLED))
39 		return -ENODEV;
40 
41 	if (lapic->processor_id != acpi_id)
42 		return -EINVAL;
43 
44 	*apic_id = lapic->id;
45 	return 0;
46 }
47 
map_x2apic_id(struct acpi_subtable_header * entry,int device_declaration,u32 acpi_id,phys_cpuid_t * apic_id)48 static int map_x2apic_id(struct acpi_subtable_header *entry,
49 		int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
50 {
51 	struct acpi_madt_local_x2apic *apic =
52 		container_of(entry, struct acpi_madt_local_x2apic, header);
53 
54 	if (!(apic->lapic_flags & ACPI_MADT_ENABLED))
55 		return -ENODEV;
56 
57 	if (device_declaration && (apic->uid == acpi_id)) {
58 		*apic_id = apic->local_apic_id;
59 		return 0;
60 	}
61 
62 	return -EINVAL;
63 }
64 
map_lsapic_id(struct acpi_subtable_header * entry,int device_declaration,u32 acpi_id,phys_cpuid_t * apic_id)65 static int map_lsapic_id(struct acpi_subtable_header *entry,
66 		int device_declaration, u32 acpi_id, phys_cpuid_t *apic_id)
67 {
68 	struct acpi_madt_local_sapic *lsapic =
69 		container_of(entry, struct acpi_madt_local_sapic, header);
70 
71 	if (!(lsapic->lapic_flags & ACPI_MADT_ENABLED))
72 		return -ENODEV;
73 
74 	if (device_declaration) {
75 		if ((entry->length < 16) || (lsapic->uid != acpi_id))
76 			return -EINVAL;
77 	} else if (lsapic->processor_id != acpi_id)
78 		return -EINVAL;
79 
80 	*apic_id = (lsapic->id << 8) | lsapic->eid;
81 	return 0;
82 }
83 
84 /*
85  * Retrieve the ARM CPU physical identifier (MPIDR)
86  */
map_gicc_mpidr(struct acpi_subtable_header * entry,int device_declaration,u32 acpi_id,phys_cpuid_t * mpidr)87 static int map_gicc_mpidr(struct acpi_subtable_header *entry,
88 		int device_declaration, u32 acpi_id, phys_cpuid_t *mpidr)
89 {
90 	struct acpi_madt_generic_interrupt *gicc =
91 	    container_of(entry, struct acpi_madt_generic_interrupt, header);
92 
93 	if (!(gicc->flags & ACPI_MADT_ENABLED))
94 		return -ENODEV;
95 
96 	/* device_declaration means Device object in DSDT, in the
97 	 * GIC interrupt model, logical processors are required to
98 	 * have a Processor Device object in the DSDT, so we should
99 	 * check device_declaration here
100 	 */
101 	if (device_declaration && (gicc->uid == acpi_id)) {
102 		*mpidr = gicc->arm_mpidr;
103 		return 0;
104 	}
105 
106 	return -EINVAL;
107 }
108 
109 /*
110  * Retrieve the RISC-V hartid for the processor
111  */
map_rintc_hartid(struct acpi_subtable_header * entry,int device_declaration,u32 acpi_id,phys_cpuid_t * hartid)112 static int map_rintc_hartid(struct acpi_subtable_header *entry,
113 			    int device_declaration, u32 acpi_id,
114 			    phys_cpuid_t *hartid)
115 {
116 	struct acpi_madt_rintc *rintc =
117 	    container_of(entry, struct acpi_madt_rintc, header);
118 
119 	if (!(rintc->flags & ACPI_MADT_ENABLED))
120 		return -ENODEV;
121 
122 	/* device_declaration means Device object in DSDT, in the
123 	 * RISC-V, logical processors are required to
124 	 * have a Processor Device object in the DSDT, so we should
125 	 * check device_declaration here
126 	 */
127 	if (device_declaration && rintc->uid == acpi_id) {
128 		*hartid = rintc->hart_id;
129 		return 0;
130 	}
131 
132 	return -EINVAL;
133 }
134 
135 /*
136  * Retrieve LoongArch CPU physical id
137  */
map_core_pic_id(struct acpi_subtable_header * entry,int device_declaration,u32 acpi_id,phys_cpuid_t * phys_id)138 static int map_core_pic_id(struct acpi_subtable_header *entry,
139 		int device_declaration, u32 acpi_id, phys_cpuid_t *phys_id)
140 {
141 	struct acpi_madt_core_pic *core_pic =
142 		container_of(entry, struct acpi_madt_core_pic, header);
143 
144 	if (!(core_pic->flags & ACPI_MADT_ENABLED))
145 		return -ENODEV;
146 
147 	/* device_declaration means Device object in DSDT, in LoongArch
148 	 * system, logical processor acpi_id is required in _UID property
149 	 * of DSDT table, so we should check device_declaration here
150 	 */
151 	if (device_declaration && (core_pic->processor_id == acpi_id)) {
152 		*phys_id = core_pic->core_id;
153 		return 0;
154 	}
155 
156 	return -EINVAL;
157 }
158 
map_madt_entry(struct acpi_table_madt * madt,int type,u32 acpi_id)159 static phys_cpuid_t map_madt_entry(struct acpi_table_madt *madt,
160 				   int type, u32 acpi_id)
161 {
162 	unsigned long madt_end, entry;
163 	phys_cpuid_t phys_id = PHYS_CPUID_INVALID;	/* CPU hardware ID */
164 
165 	if (!madt)
166 		return phys_id;
167 
168 	entry = (unsigned long)madt;
169 	madt_end = entry + madt->header.length;
170 
171 	/* Parse all entries looking for a match. */
172 
173 	entry += sizeof(struct acpi_table_madt);
174 	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
175 		struct acpi_subtable_header *header =
176 			(struct acpi_subtable_header *)entry;
177 		if (header->type == ACPI_MADT_TYPE_LOCAL_APIC) {
178 			if (!map_lapic_id(header, acpi_id, &phys_id))
179 				break;
180 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC) {
181 			if (!map_x2apic_id(header, type, acpi_id, &phys_id))
182 				break;
183 		} else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC) {
184 			if (!map_lsapic_id(header, type, acpi_id, &phys_id))
185 				break;
186 		} else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT) {
187 			if (!map_gicc_mpidr(header, type, acpi_id, &phys_id))
188 				break;
189 		} else if (header->type == ACPI_MADT_TYPE_RINTC) {
190 			if (!map_rintc_hartid(header, type, acpi_id, &phys_id))
191 				break;
192 		} else if (header->type == ACPI_MADT_TYPE_CORE_PIC) {
193 			if (!map_core_pic_id(header, type, acpi_id, &phys_id))
194 				break;
195 		}
196 		entry += header->length;
197 	}
198 	return phys_id;
199 }
200 
acpi_map_madt_entry(u32 acpi_id)201 phys_cpuid_t __init acpi_map_madt_entry(u32 acpi_id)
202 {
203 	struct acpi_table_madt *madt = NULL;
204 	phys_cpuid_t rv;
205 
206 	acpi_get_table(ACPI_SIG_MADT, 0,
207 		       (struct acpi_table_header **)&madt);
208 	if (!madt)
209 		return PHYS_CPUID_INVALID;
210 
211 	rv = map_madt_entry(madt, 1, acpi_id);
212 
213 	acpi_put_table((struct acpi_table_header *)madt);
214 
215 	return rv;
216 }
217 
map_mat_entry(acpi_handle handle,int type,u32 acpi_id)218 static phys_cpuid_t map_mat_entry(acpi_handle handle, int type, u32 acpi_id)
219 {
220 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
221 	union acpi_object *obj;
222 	struct acpi_subtable_header *header;
223 	phys_cpuid_t phys_id = PHYS_CPUID_INVALID;
224 
225 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
226 		goto exit;
227 
228 	if (!buffer.length || !buffer.pointer)
229 		goto exit;
230 
231 	obj = buffer.pointer;
232 	if (obj->type != ACPI_TYPE_BUFFER ||
233 	    obj->buffer.length < sizeof(struct acpi_subtable_header)) {
234 		goto exit;
235 	}
236 
237 	header = (struct acpi_subtable_header *)obj->buffer.pointer;
238 	if (header->type == ACPI_MADT_TYPE_LOCAL_APIC)
239 		map_lapic_id(header, acpi_id, &phys_id);
240 	else if (header->type == ACPI_MADT_TYPE_LOCAL_SAPIC)
241 		map_lsapic_id(header, type, acpi_id, &phys_id);
242 	else if (header->type == ACPI_MADT_TYPE_LOCAL_X2APIC)
243 		map_x2apic_id(header, type, acpi_id, &phys_id);
244 	else if (header->type == ACPI_MADT_TYPE_GENERIC_INTERRUPT)
245 		map_gicc_mpidr(header, type, acpi_id, &phys_id);
246 	else if (header->type == ACPI_MADT_TYPE_CORE_PIC)
247 		map_core_pic_id(header, type, acpi_id, &phys_id);
248 
249 exit:
250 	kfree(buffer.pointer);
251 	return phys_id;
252 }
253 
acpi_get_phys_id(acpi_handle handle,int type,u32 acpi_id)254 phys_cpuid_t acpi_get_phys_id(acpi_handle handle, int type, u32 acpi_id)
255 {
256 	phys_cpuid_t phys_id;
257 
258 	phys_id = map_mat_entry(handle, type, acpi_id);
259 	if (invalid_phys_cpuid(phys_id))
260 		phys_id = map_madt_entry(get_madt_table(), type, acpi_id);
261 
262 	return phys_id;
263 }
264 EXPORT_SYMBOL_GPL(acpi_get_phys_id);
265 
acpi_map_cpuid(phys_cpuid_t phys_id,u32 acpi_id)266 int acpi_map_cpuid(phys_cpuid_t phys_id, u32 acpi_id)
267 {
268 #ifdef CONFIG_SMP
269 	int i;
270 #endif
271 
272 	if (invalid_phys_cpuid(phys_id)) {
273 		/*
274 		 * On UP processor, there is no _MAT or MADT table.
275 		 * So above phys_id is always set to PHYS_CPUID_INVALID.
276 		 *
277 		 * BIOS may define multiple CPU handles even for UP processor.
278 		 * For example,
279 		 *
280 		 * Scope (_PR)
281 		 * {
282 		 *     Processor (CPU0, 0x00, 0x00000410, 0x06) {}
283 		 *     Processor (CPU1, 0x01, 0x00000410, 0x06) {}
284 		 *     Processor (CPU2, 0x02, 0x00000410, 0x06) {}
285 		 *     Processor (CPU3, 0x03, 0x00000410, 0x06) {}
286 		 * }
287 		 *
288 		 * Ignores phys_id and always returns 0 for the processor
289 		 * handle with acpi id 0 if nr_cpu_ids is 1.
290 		 * This should be the case if SMP tables are not found.
291 		 * Return -EINVAL for other CPU's handle.
292 		 */
293 		if (nr_cpu_ids <= 1 && acpi_id == 0)
294 			return acpi_id;
295 		else
296 			return -EINVAL;
297 	}
298 
299 #ifdef CONFIG_SMP
300 	for_each_possible_cpu(i) {
301 		if (cpu_physical_id(i) == phys_id)
302 			return i;
303 	}
304 #else
305 	/* In UP kernel, only processor 0 is valid */
306 	if (phys_id == 0)
307 		return phys_id;
308 #endif
309 	return -ENODEV;
310 }
311 
acpi_get_cpuid(acpi_handle handle,int type,u32 acpi_id)312 int acpi_get_cpuid(acpi_handle handle, int type, u32 acpi_id)
313 {
314 	phys_cpuid_t phys_id;
315 
316 	phys_id = acpi_get_phys_id(handle, type, acpi_id);
317 
318 	return acpi_map_cpuid(phys_id, acpi_id);
319 }
320 EXPORT_SYMBOL_GPL(acpi_get_cpuid);
321 
322 #ifdef CONFIG_ACPI_HOTPLUG_IOAPIC
get_ioapic_id(struct acpi_subtable_header * entry,u32 gsi_base,u64 * phys_addr,int * ioapic_id)323 static int get_ioapic_id(struct acpi_subtable_header *entry, u32 gsi_base,
324 			 u64 *phys_addr, int *ioapic_id)
325 {
326 	struct acpi_madt_io_apic *ioapic = (struct acpi_madt_io_apic *)entry;
327 
328 	if (ioapic->global_irq_base != gsi_base)
329 		return 0;
330 
331 	*phys_addr = ioapic->address;
332 	*ioapic_id = ioapic->id;
333 	return 1;
334 }
335 
parse_madt_ioapic_entry(u32 gsi_base,u64 * phys_addr)336 static int parse_madt_ioapic_entry(u32 gsi_base, u64 *phys_addr)
337 {
338 	struct acpi_subtable_header *hdr;
339 	unsigned long madt_end, entry;
340 	struct acpi_table_madt *madt;
341 	int apic_id = -1;
342 
343 	madt = get_madt_table();
344 	if (!madt)
345 		return apic_id;
346 
347 	entry = (unsigned long)madt;
348 	madt_end = entry + madt->header.length;
349 
350 	/* Parse all entries looking for a match. */
351 	entry += sizeof(struct acpi_table_madt);
352 	while (entry + sizeof(struct acpi_subtable_header) < madt_end) {
353 		hdr = (struct acpi_subtable_header *)entry;
354 		if (hdr->type == ACPI_MADT_TYPE_IO_APIC &&
355 		    get_ioapic_id(hdr, gsi_base, phys_addr, &apic_id))
356 			break;
357 		else
358 			entry += hdr->length;
359 	}
360 
361 	return apic_id;
362 }
363 
parse_mat_ioapic_entry(acpi_handle handle,u32 gsi_base,u64 * phys_addr)364 static int parse_mat_ioapic_entry(acpi_handle handle, u32 gsi_base,
365 				  u64 *phys_addr)
366 {
367 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
368 	struct acpi_subtable_header *header;
369 	union acpi_object *obj;
370 	int apic_id = -1;
371 
372 	if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
373 		goto exit;
374 
375 	if (!buffer.length || !buffer.pointer)
376 		goto exit;
377 
378 	obj = buffer.pointer;
379 	if (obj->type != ACPI_TYPE_BUFFER ||
380 	    obj->buffer.length < sizeof(struct acpi_subtable_header))
381 		goto exit;
382 
383 	header = (struct acpi_subtable_header *)obj->buffer.pointer;
384 	if (header->type == ACPI_MADT_TYPE_IO_APIC)
385 		get_ioapic_id(header, gsi_base, phys_addr, &apic_id);
386 
387 exit:
388 	kfree(buffer.pointer);
389 	return apic_id;
390 }
391 
392 /**
393  * acpi_get_ioapic_id - Get IOAPIC ID and physical address matching @gsi_base
394  * @handle:	ACPI object for IOAPIC device
395  * @gsi_base:	GSI base to match with
396  * @phys_addr:	Pointer to store physical address of matching IOAPIC record
397  *
398  * Walk resources returned by ACPI_MAT method, then ACPI MADT table, to search
399  * for an ACPI IOAPIC record matching @gsi_base.
400  * Return IOAPIC id and store physical address in @phys_addr if found a match,
401  * otherwise return <0.
402  */
acpi_get_ioapic_id(acpi_handle handle,u32 gsi_base,u64 * phys_addr)403 int acpi_get_ioapic_id(acpi_handle handle, u32 gsi_base, u64 *phys_addr)
404 {
405 	int apic_id;
406 
407 	apic_id = parse_mat_ioapic_entry(handle, gsi_base, phys_addr);
408 	if (apic_id == -1)
409 		apic_id = parse_madt_ioapic_entry(gsi_base, phys_addr);
410 
411 	return apic_id;
412 }
413 #endif /* CONFIG_ACPI_HOTPLUG_IOAPIC */
414